View source for Herpes zoster ophthalmicus

==Background==
*Occurs when [[varicella zoster virus]] is reactivated in the ophthalmic division (V1) of trigeminal nerve
*50% of cases associated with ocular involvement
**Highly suggested by vesicles at tip of nose (Hutchinson's sign)
**Nasociliary branch of V1 innervates both the lateral/tip of nose as well as the cornea
*Consider immunocompromise in patients <40yrs

{{Herpes viruses}}
{{Conjunctivitis DDX}}

==Clinical Features==
[[File:Herpes zoster ophthalmicus2.jpg|thumb|Herpes zoster ophthalmicus]]
*Prodrome of [[headache]], malaise, photophobia, [[fever]]
*Unilateral [[eye pain|pain]] or hypesthesia in V1 distribution
*Hyperemic [[conjunctivitis]], [[episcleritis]], lid droop
*Vesicular [[rash]] in V1 distribution
*[[Slit-lamp exam]]:
**Initial finding of punctate epithelial keratitis that then evolves into pseudodendrite<ref>Li, J. Y. (2018). Herpes zoster ophthalmicus. Current Opinion in Ophthalmology, 29(4), 328–333. doi:10.1097/icu.0000000000000491 </ref>
**Pseudodendrite (poorly staining mucous plaque with no epithelial erosion)
***In contrast to [[HSV]] which has true dendrite with epithelial erosion and staining
**Cell and flare

==Differential Diagnosis==
{{VZV types}}
{{HIV associated conditions}}
{{Unilateral red eye DDX}}
{{Bilateral Red Eyes}}

==Evaluation==
*Clinical

==Management==
*Cool compresses/lubrication drops
*Topical [[antibiotics]] to skin to prevent secondary infection
*Antiviral therapy indicated for rash <1wk duration
**[[Acyclovir]] IV 10mg/kg q8hrs x7-10 days<ref>Wills Eye Manual, 6th edition</ref> '''OR'''
**[[Famciclovir]] 500mg PO q8hrs x14 days '''OR'''
**[[Valacyclovir]] 1g PO q8hrs
*Prevention of reactivation
**[[Acyclovir]] PO 500mg 5x per day
*Ophtho consultation regarding steroid use

==Disposition==
*Immunocompetent patient: Oral antiviral.
*Immunocompromised patient: ”IV acyclovir and hospitalization is recommended. Neuroimaging is advised in patients with vision loss.”<ref>SAEM Clinical Image Series: A Case of a Painful Facial Rash. J Chan, et al. Aliem accessed Dec 16, 2019 available online at https://www.aliem.com/2019/12/saem-clinical-image-series-facial-rash/ </ref>

==See Also==
*[[Herpes zoster oticus]]

==References==
<references/>

[[Category:ID]]
[[Category:Ophthalmology]]